Convert string16 to use base namespace.

TBR=sky

Review URL: https://codereview.chromium.org/109233002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239538 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 239538
cc: Inline GLRenderer::Initialize into the constructor

Since the method can no longer fail, no reason to delay it and force
unit tests to all call it.

Depends on: https://codereview.chromium.org/107193003/

R=jamesr
BUG=

Review URL: https://codereview.chromium.org/108313003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239540 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 239540